Spotify vs. Apple Music vs. Google Play vs. Tidal: Which is Best

For me, Spotify and it is not close. I use streaming exclusively for music discovery and Spotify is far better at that. If I like an album sufficiently to want to listen on unbridled quality, I buy it. 

I've never tried Spotify so can't say that Tidal is "better", but I chose Tidal because of the availability of Master quality albums.  I do almost all my Tidal listening on decent systems and can hear noticeable differences in sound quality when comparing most of the Master quality albums vs their "HI-FI" versions even when not using a MQA capable device.  I wish Tidal catered more to my musical tastes (classic rock, jazz, electronic) and was easier to browse by those categories, but I can usually find anything I want through the search function.  

Go with MUSCONV tool to sync music files from one music stream to other such as amazon music to google play, tidal to spotify,  itunes to spotify, and more..

I can say that spotify and apple Music is the best among other based on my experience. And MUSCONV is the tool to import spotify to itunes, google play to tidal, and etc

Somebody earlier stated the Tidal interface on the desktop was poor and I somewhat agree.
I stream Tidal via my Bluesound Vault which means using the android Bluos app rather than the Tidal app.
I have compared the Tidal android app to the Tidal functionality inside the Bluos app and it is no contest.
Using Tidal inside the Bluos app is far superior to Tidal own app which yes is odd but there it is!

And as far as SQ, Tidal by a landslide.
Some complain of the search functions and limited jazz/classical library.
I have never had an issue with search and do not listen to jazz or classical so cannot comment but can state that their rock library is much larger than Deezer or Quboz right now.